KIT METHOD OF PREPARATION OF 4-IODOANTIPYRINE (I-123) FROM NA-I-123

Abstract

4-Iodoantipyrine (4-IAP), containing 123I, was suggested as a radiopharmaceutical for direct imaging of human regional cerebral perfusion. In routine clinical use, a reliable source of the labeled compound was required. The 4-IAP (123I) was prepared by exchange between Na123I and 4-bromoantipyrine (4-BrAP) or 4-IAP with heating in aqueous acidic solution. Using an H3PO4 buffer system at pH 2.5 during labeling, with addition of NaOH for subsequent buffering at pH 7.0, a convenient reliable kit for routine preparation of 4-IAP (123I) from commercially available Na123I was developed.